Different Ethnicities Have Distinct Mouth Microbes

By Breanna Draxler | October 25, 2013 1:00 pm

oral microbiomes

Despite obsessive brushing, flossing and mouthwashing, your mouth is (and will always be) filled with bacteria. Lots of them. These bugs play a role in determining if you’ll get cavities, gum disease and maybe even oral cancer. Of course what you eat and how often you drag yourself to the dentist can impact who sets up camp in your chomper, but do your genes have a say, too? New research says yes, and that the particular mix is specific to your ethnicity.

Rinse, Spit, Repeat

Researchers collected spit and plaque samples from 100 Americans who fell into four ethnic categories: non-Hispanic blacks, non-Hispanic whites, Chinese and Latinos. Every one of the participants had two percent of their bacteria in common—what the researchers called a core community.

Beyond that, though, each individual’s microbiome was unique, like a fingerprint. Even more surprising was the fact that each ethnicity showed a unique mix of bacterial species that populated the mouths of each of its 25 individuals. Science Daily quoted the researcher saying,

“This is the first time it has been shown that ethnicity is a huge component in determining what you carry in your mouth. We know that our food and oral hygiene habits determine what bacteria can survive and thrive in our mouths, which is why your dentist stresses brushing and flossing. Can your genetic makeup play a similar role? The answer seems to be yes, it can,” said Purnima Kumar.

Getting Personal

Such signatures could predispose people to particular diseases, and help dentists prescribe patient-specific care. It may not be fun—what oral hygiene ever is?—but it could be more effective than the typical “brush and floss” mantra.

Image by CREATISTA / Shutterstock

CATEGORIZED UNDER: Health & Medicine, top posts
  • JH

    Over 60 years ago my mother was involved in research at the University of Michigan. I do not know all the particulars but she often told me that you could change the bacteria in your mouth by changing your diet. This was of particular interest to her since she was in dentistry. I was one of her unofficial test cases. I’ve never had a cavity. And that wasn’t because of my ethnicity or, I’m embarrassed to say, my good oral hygiene habits. I’m wondering if ethnic food choices might play an important role in the above research?

    • Breanna Draxler

      Thanks for sharing, JH. Food does impact a person’s oral microbiome, but in this case the researchers were looking specifically at ethnicity on the genetic level and how it impacted microbes in the mouth. So while people of a particular ethnicity may tend to eat similar foods, these findings go beyond dietary influence.

      • alqpr

        How do you know that? If they did anything to isolate the genetic effect why doesn’t your article explain what that was? Totally useless!!

        • Breanna Draxler

          I was trying to communicate the overall findings without getting bogged down by details of the study’s methodology. For those of you interested in reading specifically how researchers came to their genetic conclusions, the paper is available for free: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077287

          • alqpr

            Well that’s a cop-out!

  • http://blogs.discovermagazine.com Carol Thompson

    This study presented no findings relating to genes whatsoever. It ignores obvious factors such as kissing family members as a primary source of oral bacteria. Therefore the claims are mere speculation with no credibility.

    • Breanna Draxler

      While this blog post doesn’t get into the details of the study’s methodology, the researchers’ peer-reviewed paper (linked in the post above and pasted below) describes the process and findings in detail. You can read it for free here: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077287

      • alqpr

        Well, I shouldn’t have had to do that but I did. And so far as I can see, Carol Thompson is right. The study presented no actual findings relating to genes whatsoever, and made no rigorous attempt to isolate the effects of confounding factors. So your bit about “do your genes have a say, too? New research says yes” is quite wrong.

        The best that is in there is just idle speculation based on a really shocking presumption “This is interesting because although African Americans and Caucasians have shared similar environmental factors including food, nutrition, and lifestyle over several generations,”<–yes, they really said that!!! "(unlike Chinese and Latino subjects who were either immigrants or first generation residents), they demonstrated distinct microbial communities. This suggests that the host genotype influences the microbial community to a greater extent than shared environment;"

        Even if the presumption were true, it would be quite wrong to go from that 'suggestion' to using the word 'demonstrates' in their concluding discussion where they say "Our data demonstrates that ethnicity exerts a selection pressure on the oral microbiome, and that this selection pressure is genetic rather than environmental, since the two ethnicities that shared a common food, nutritional and lifestyle heritage (Caucasians and African Americans) demonstrated significant microbial divergence."

  • Gary Vardon

    There are many racial differences. This is one of many. Racial differences are worth studying.

  • Octavus5

    This is ridiculous on the face of it. More likely, the differences in microbes are due to food and other cultural/ethnic habits.

    • Arsaces

      My thoughts exactly. Different cultures have different types of foods and drinks. Genes probally also have some part to play (Especially when it comes to enzymes), but I doubt it is that big.

      In addition, your stomach also has a big role to play when it comes to the bacteria in your mouth.

  • livvylrq273

    My Uncle Nolan got a fantastic cream Chevrolet Camaro Convertible only from working part time off a pc at home. published here……..WWW.JOBS.COM


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